This link shows the 4 types of nerve axons/fibers that go back to the spinal cord and brain carrying sensory information:

http://faculty.washington.edu/chudler/cv.html

The long tail on the illustrated neuron, that is animated is the axon. Of the 4 types of sensory fibers, 3 are myelinated, which are insulated with a type of fat. (shows in yellow).
The C fibers are the slowest and do not have this protection.

Your diagnosis is that you have a sensory problem with damage to or poor functioning of the axons, which relay information to the spinal cord.

This is descriptive only, and does not explain what or how this is happening. So as a diagnosis it tells very little.

possibilities:
toxin
drug
vaccine
autoimmune attacks
infectious (viral or bacterial)
DNA damage or genetic failure to repair (CMT)
mitochondrial damage
diabetes
cancer (paraneoplasia)
Allergic (gluten intolerance, histamine)

So as a diagnosis this only describes the loss of function but
not what is causing it.